Discover all Calibre features


Pull Request Reviews

Compare and see the performance impact of your team’s work without leaving GitHub.

Test Profiles

Change conditions that Calibre tests your Sites in—connection speed, devices, test location and more.

Performance Budgets

Track your progress and introduce accountability by setting budgets against metrics.

Single Page Tests

Quickly create and share one-off test results with no log-in required.

Insights Email Report

Receive comprehensive performance overviews directly to your inbox each week.

Google Lighthouse built-in

Leverage the power of a custom-built performance suite, including Google Lighthouse.

Core Web Vitals support

Track modern metrics that will have an impact on your search ranking: Largest Contentful Paint, Cumulative Layout Shift and Total Blocking Time.

Main Thread Execution Timeline

Easily identify tasks that are long-running or blocking the JavaScript main thread execution.

Third Party Tracking

Understand the impact of external scripts—how it affects your page size and execution time.

Pages Leaderboard

Find best or worst performing Pages and benchmark against your competitors.

Global testing infrastructureNew

Test your Sites across 17 global locations to discover where your customers’ experience suffers most.

Unlimited data retention

We offer a lifetime snapshot data retention for all account tiers.

Advanced test scheduling

Always be in control of how often your Sites should be tested.

Test variability prevention

Be confident in your metrics with an AI-powered test verification engine that quickly re-tests results when an anomaly is detected.

Unlimited Sites and Pages

Track unlimited Sites and Pages at no extra cost.

Metric charts

See historical performance metric data over up to 6 months.

Ad and Third Party Blocking

Block ads and third party resources to establish a performance baseline.

JavaScript timings

Find out the parse, compile and execution cost of internal and vendor scripts.

Testing authenticated pages

Access Pages requiring authentication through cookies, custom headers or form log-ins.

Site render timeline

Easily spot when and under which conditions rendering problems occur.

Fixed IP addresses

Use fixed IP addresses to ensure requests are securely coming from Calibre.

Request log

Dig into downloaded assets and learn how to optimise their delivery.

HAR files

Download HAR files to understand connectivity and transfer issues.


Command line interface

Automate your performance system with powerful, modern CLI tooling.

Node.js API

Use our npm package to leverage Calibre directly in Node.


Add webhooks to retrieve snapshot data securely through HTTP.

Deploy tracking

Find out which release affected performance, accessibility or SEO with deployment markers.


Email alerts

Get timely notifications about your performance monitoring and data, from performance budgets to test failures.

Slack integration

Receive instant alerts about new snapshots or performance budgets being met or blown.



Use Pull Request Reviews without any additional work when deploying Jamstack applications and websites.


Trigger Snapshots after a Netlify deploy and mark releases on your metric charts.


Send metrics from Calibre to Geckoboard to visualise your performance KPIs in your office.

Security and privacy

Full encryption

We encrypt all of your data at rest in both our databases and file storage.

GDPR compliance

We comply with the General Data Protection Regulation (GDPR) to ensure you always have control over your data.

Google (SSO)New

Sign up and log in with your Google account on every Plan tier.

SSO (SAML)Enterprise

Add an extra layer of sign in security and faster onboarding for your organisation with tools like Okta, OneLogin and more.

Try the most advanced performance suite